Malicious PDF — malware analysis report

Static analysis result for SHA-256 44f16f8ae81beb1a…

MALICIOUS

PDF

83.9 KB Created: 2021-06-10 03:31:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 43806d1e0bbebe79273058be80c8456f SHA-1: c8554006a64f8f8f325ddc81d7df3bd140e52c78 SHA-256: 44f16f8ae81beb1a866990308d3c72bbaf4b632c114424e2a445a6d5ebe4ef80
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs pointing to compromised WordPress sites, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple distinct hosts and UTM parameters in the URLs reinforces the link farm pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ketchas.ru/uplcv?utm_term=c+%2526+c+pawn+shop PDF link annotation
    • http://sooclose.eu/upload/File/40248286845.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b98c8cce56c---9904803472.pdfIn PDF document text
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/n5rief4kj2v4hr6ud2k4okl1uf/33991010822.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606f72de5c280---61663123483.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/hbrvgskm9mf1m9ge7vcraj5m75/87710235550.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b11beea2066---pamudetuwibojas.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608b4587d7ab3---lavozuzuwirilasoravezinol.pdfIn PDF document text
    • http://sghscsjamarai.org/guruhargobind/userfiles/file/foduwilipijumunub.pdfIn PDF document text
    • http://vietthanhstone.com/images/news/file/raludakuzisajodave.pdfIn PDF document text
    • https://flexrocksrollovers.com/wp-content/plugins/super-forms/uploads/php/files/f09inurpp7rr93p79id35tl6oj/vodixelina.pdfIn PDF document text
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/fd0e3e0a434c406c8e73b5a5525385cc/5695036418.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/9d1abcf66868ffedf6544b5cbdc6b62d/46251365373.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/f30d0e7c34015847496b7d4523d69dbe/miwaredotebep.pdfIn PDF document text
    • https://www.spreefahrten-berlin.de/wp-content/plugins/super-forms/uploads/php/files/1r3o8kp7hbr3rk538o3e42rapa/99969400266.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e70a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE70A 4064 bytes
SHA-256: 64acb3b29b6311d5fbdd8744e0888efcfdd667446498830d0533765eae80b708
font_01_sfnt_off0000f4cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4CF 1988 bytes
SHA-256: d808236ebbf49d78ac1711b84e6d17f26e9f3762cc71dac098008ae91580bd1e
font_02_sfnt_off0000fe67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE67 15680 bytes
SHA-256: 05a942638d7cc6dcfe472714816996eb3ce2526cbf163939555f2574fc95763b
font_03_sfnt_off00012da0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DA0 16304 bytes
SHA-256: 37547abd9e99d79399a3acda8f74bd808e1ac84f80caca52180ee1517460d801